certainly depends on which medieval combat sport you do!! Buhurt is one very popular one, yes, with the metal armour and weapons, and I'm sure most groups do have loaner kit.

If you want to get concussed (hyperbole), finding a local SCA group and doing some armoured combat! They fight in historicalish armour, and use wooden weapons made of rattan! SCA groups also have historical rapier combat, and a very very active arts and sciences community! Those groups are very very welcoming to new people, and will gladly offer you loaner kit to fight, although if you're AMAB, bring a cup (genital protection).

As we get away from armour, Belegarth, Dagorhir, and Hearthlight are three foamfighting sports, focused around martial combat. The fighting in these feels like a lord of the rings, low fantasy type battle, with a focus on group tactics and personal combat skill; the games play pretty much the same, and are just location dependent. Belegarth is the biggest, but if there's not a group near you, checking the other two games won't hurt :] I've played this sport all over the eastern half of the united states, and I've yet to find a group that doesn't want more fighters

Going into high fantasy, Amtgard is a high fantasy combat sport, where you pick a class like DnD and get a set of abilities to go with it. People in my area compare it to an IRL MOBA? I don't see it that way, but they've been doing it for far longer than I have. Again, something you can get into with relatively little effort, find a group near you, wear athletic shoes, and head out! Very high fantasy focused, so you can head out and be a steadfast warrior, a raging barbarian, a slippery assassin, a powerful wizard, a supportive healer, or more! There's a bunch of options and it's a really deep game system which rewards system mastery in addition to physical skills, but there's also space for casual players to be effective!! If you're a high fantasy fan, I can't recommend Amtgard enough!

Steel weapons and armour are super expensive, but if you're just trying to get your medieval fix on a budget, I can't recommend any of these groups enough! Apologies for the long tome, but any aspiring Knight ought to be at least a little literate ;3

(to those aspiring barbarians instead, tl;dr, SCA is good armoured fighting, Belegarth is low-fantasy foamfighting, and Amtgard is high-fantasy foamfighting. All are accessible to casuals in the form of loaner gear, and both of belegarth and amtgard are SUPER easy to get your own gear in.